The present application relates generally to methods and/or systems for electronically magnifying a target object, such as the page of a book. Electronic magnifiers perform image processing in real time to display a magnified image of the target object and are particularly useful to the visually impaired. The devices allow the visually impaired to see small writing in long and short documents, such as medicine bottles, recipes, menus, food labels, correspondences, books and magazines.
While the visually impaired have traditionally made use of magnifying glasses, electronic magnifiers have a number of benefits that make them more attractive than traditional magnifiers. See Anne Eisenberg, The Magnifying Glass Gets an Electronic Twist, N.Y. TIMES, May 25, 2008. Namely, electronic magnifiers have the ability to modify contrast, brightness, hue, etc., which traditional magnifiers lack. Additionally, electronic magnifiers have the ability to change the color of backgrounds and lettering. For example, electronic magnifiers can change black lettering and a white background to a black background and white lettering, which may be advantageous to people with macular degeneration.
However, there are two main hurdles holding electronic magnifiers back: cost and usability. These hurdles stem from a need to properly focus on the target object. Naturally, a magnifier isn't useful if it cannot provide a clear, magnified image. Illustrating these hurdles, two known approaches to achieving electronic magnification are presented.
One approach is to adjust magnification by moving the device closer/farther to/from the target object. This approach relies on an autofocus lens capable of adjusting focus over a large range of small distances. The usability of this approach is very high because it closely approximates a magnifying glass and is intuitive to use. However, this approach is quite costly, relative to a traditional magnifying glass, due to the fact that it requires an autofocus lens. Additionally, most existing imaging devices, such as camera phones, lack such an autofocus lens. One would have to purchase a separate device equipped with an autofocus lens to carry out this approach. Thus, this approach has high usability, but the usability comes at the price of a high cost.
Another approach is to hold a camera far enough from the target object such that the target object can be imaged in focus. With such an approach, the user simply uses manual controls to adjust the zoom of the image. Likewise, the user simply pans by moving the imaging device. As should be apparent, this approach is beneficial in that it does not require an expensive lens and is compatible with most existing imaging devices. Namely, one could make use of their camera phone and/or some other portable handheld device they already own. However, this approach presents challenges to the user because at useful magnifications, small directional changes will move the field of view of the camera a large amount, and the image will be shaky. Thus, this approach does not have a high usability, but it is relatively inexpensive.
In view of the foregoing discussion, an approach that is both inexpensive and highly usable is desirable. The present application contemplates a new and improved system and/or method which overcomes the above-referenced problems and others.